Burn patients find relief in a virtual world

The 17-year-old boy had deep flash burns covering a third of his body. When his dressings were changed each day, the pain was almost intolerable, even with strong doses of opioid painkillers. Finally, he found relief, from a spider--a virtual tarantula in a virtual kitchen.

The boy was among the first to participate in research led by psychologists David R. Patterson, PhD, and Hunter G. Hoffman, PhD, of the University of Washington's Harborview Burn Center and the university's Human Interface Technology Laboratory, respectively. They and their co-workers are testing the effectiveness of using immersive virtual reality, in addition to traditional narcotics, to control burn patients' pain during wound care and physical therapy.

So far, the team has met with considerable success. They hope that if further studies continue to show positive results, and as technology advances, virtual reality will become a standard tool in the nation's hospitals and burn centers.

"Patients have a right to better pain management," says Hoffman. "It's not a luxury--it is a right. And the problem is not limited to burn wound care." Ultimately, he suggests, virtual reality may also be used to help control pain in other situations, such as during cancer treatment, painful dental procedures, childbirth and physical therapy following surgery.

Calling the research "refreshing," University of Tennessee psychologist Michael Nash, PhD, editor of the International Journal of Clinical and Experimental Hypnosis, suggests that further studies should address clinical questions about which patients are most helped by the therapy and under what circumstances it is most effective, as well as more basic neuroscience questions concerning how virtual reality draws attention away from pain.

"At this point, it's a wide-open field," Nash says.

Moving the attentional 'spotlight'

Patterson and Hoffman's collaboration is the product of Patterson's longstanding interest in hypnotic analgesia--hypnosis has long-been shown to be an effective method for controlling many kinds of pain, in people who are easy to hypnotize--and Hoffman's background in attention and cognition and their role in virtual reality.

At their roots, hypnotic analgesia and the newer use of virtual reality to control pain both seek to distract patients from their pain. But whereas hypnosis relies on patients' imaginative absorption and responsiveness to suggestion, Patterson explains, virtual reality uses technology to shift patients' attentional "spotlight" away from their pain. Virtual reality, Patterson and Hoffman suspected, might be especially conducive to controlling pain in children and adolescents, who appear especially intrigued by technological wizardry.

The researchers' first test of virtual reality was with two teen-age burn patients, each of whom underwent a few minutes of wound treatment either while they played a Nintendo game or while they were in "SpiderWorld," a virtual environment developed for treating spider phobia.

In that initial case study, published in the journal Pain (Vol. 85, No. 1-2) in March 2000, both patients reported feeling significantly less pain and spending less time thinking about their pain while using virtual reality than while playing Nintendo. The researchers attribute the effect to a phenomenon known as "presence"--the illusion of actually going inside the virtual environment.

"Pain requires conscious attention," explains Hoffman. "Virtual reality lures attention into this virtual world, and that drains the amount of attention available to process the pain signal....Nintendo games are very sophisticated, but the illusion of presence in Nintendo [in our research] was very low, compared with the virtual reality environment."

Hoffman and Patterson replicated their initial results in a controlled study of 12 patients, published in September 2000 in the Clinical Journal of Pain (Vol. 16, No. 3). Further, a study of 22 healthy volunteers has bolstered the findings in burn patients, showing that participants experienced dramatic drops in pain induced by a blood-pressure cuff when they were in virtual reality, compared with when they were not distracted.

Finally, in a small controlled study and a case study published last year in the Clinical Journal of Pain (Vol. 17, No. 3) and the International Journal of Human-Computer Interaction (Vol. 13, No. 1), respectively, Hoffman, Patterson and colleagues found that virtual reality maintains its potency over multiple treatments and for treatments of longer duration.

Plugging in to the technology revolution

Now, the team is fine-tuning the virtual reality technology to enhance its usefulness. Recently, with funding from the Paul Allen Foundation for Medical Research and the National Institutes of Health, they developed a more compelling virtual environment than SpiderWorld, dubbed "SnowWorld." Patients immersed in SnowWorld fly through a snowy canyon shooting snowballs at snowmen, polar bears and igloos. The idea, says Hoffman, is that the snowy environment--the opposite of fire--will broaden the gulf between patients' burn pain and the object of their attention during treatment.

Although it will likely be years before virtual reality is sufficiently inexpensive and technically flexible enough to be widespread in medicine, the researchers say they're optimistic that the method will one day make a major difference in pain management.

"There are a lot of people who tell you that everyone's expecting technology to solve all the problems in the world, and that we shouldn't be too optimistic," says Hoffman. That's wise, he says--but in this case, technology may save the day.

"This work [shows] that here's a way to apply technology to something we've previously been using only drugs for," observes Hoffman. "We're no longer limited to coming up with better pharmacology--we can plug into the technological revolution."